Computer breakdowns shook American equity markets again today as malfunctioning software that feeds data between exchanges prompted Nasdaq Stock Market to halt trading in thousands of stocks and options.
Nasdaq said trading in shares it lists had been stopped amid issues at its Securities Information Processor, the feed that disseminates quotes and prices. The second-biggest stock market operator in the U.S. halted transactions in what it calls Tape C, which comprises all Nasdaq-listed securities.
The breakdown is one of a growing number of trading failures that have coincided with the expanding complexity of global financial markets. U.S. equity trading, which began with on Wall Street more than two centuries ago and was dominated by the New York Stock Exchange, has become dispersed among more than 50 computerized platforms accessible around the world.